Last month, I attended the International Fractal Art Symposium, where Christian Kleinhuis gave a talk on hybrid fractals--either alternating or interpolating functions each iteration. Since I already have an alternating functions formula in the UF formula database, I decided to write an interpolating functions formula. You can find it in lkm3.ufm and there are some sample parameter sets in lkm3.upr. The attached image is one example, interpolating between 2 Newtons functions, 2 Mandelbrot, and 2 Julia on each iteration.